Try 
my $bytecount = length pack 'C0a*', $string;

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The pack, when used this way, will wrap the original bytes in a string that, in 5.6 and above, is marked as a byte string — not UTF-8. So length will do the right thing. In earlier versions, all strings are byte strings, anyway.

In a similar manner, one can use 'U0' on 5.6 and above, to mark the resulting string as UTF-8 — again, without altering the bytes. So it's very similar to the UTF-8-twiddling routines _utf8_on and _utf8_off in Encode with 5.8 and above, except that this here is a function. For more info, see the entry on pack in a recent version of perlfunc.

In reply to Re: Portable string length in bytes by bart
in thread Portable string length in bytes by moseley

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